sound/arm/pxa2xx-pcm.c

   1 /*
   2  * linux/sound/arm/pxa2xx-pcm.c -- ALSA PCM interface for the Intel PXA2xx chip
   3  *
   4  * Author:      Nicolas Pitre
   5  * Created:     Nov 30, 2004
   6  * Copyright:   (C) 2004 MontaVista Software, Inc.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/device.h>
  16 #include <linux/slab.h>
  17 #include <linux/dma-mapping.h>
  18
  19 #include <sound/driver.h>
  20 #include <sound/core.h>
  21 #include <sound/pcm.h>
  22 #include <sound/pcm_params.h>
  23
  24 #include <asm/dma.h>
  25 #include <asm/hardware.h>
  26 #include <asm/arch/pxa-regs.h>
  27
  28 #include "pxa2xx-pcm.h"
  29
  30
  31 static const struct snd_pcm_hardware pxa2xx_pcm_hardware = {
  32         .info                   = SNDRV_PCM_INFO_MMAP |
  33                                   SNDRV_PCM_INFO_MMAP_VALID |
  34                                   SNDRV_PCM_INFO_INTERLEAVED |
  35                                   SNDRV_PCM_INFO_PAUSE,
  36         .formats                = SNDRV_PCM_FMTBIT_S16_LE,
  37         .period_bytes_min       = 32,
  38         .period_bytes_max       = 8192 - 32,
  39         .periods_min            = 1,
  40         .periods_max            = PAGE_SIZE/sizeof(pxa_dma_desc),
  41         .buffer_bytes_max       = 128 * 1024,
  42         .fifo_size              = 32,
  43 };
  44
  45 struct pxa2xx_runtime_data {
  46         int dma_ch;
  47         struct pxa2xx_pcm_dma_params *params;
  48         pxa_dma_desc *dma_desc_array;
  49         dma_addr_t dma_desc_array_phys;
  50 };
  51
  52 static int pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream,
  53                                 struct snd_pcm_hw_params *params)
  54 {
  55         struct snd_pcm_runtime *runtime = substream->runtime;
  56         struct pxa2xx_runtime_data *rtd = runtime->private_data;
  57         size_t totsize = params_buffer_bytes(params);
  58         size_t period = params_period_bytes(params);
  59         pxa_dma_desc *dma_desc;
  60         dma_addr_t dma_buff_phys, next_desc_phys;
  61
  62         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
  63         runtime->dma_bytes = totsize;
  64
  65         dma_desc = rtd->dma_desc_array;
  66         next_desc_phys = rtd->dma_desc_array_phys;
  67         dma_buff_phys = runtime->dma_addr;
  68         do {
  69                 next_desc_phys += sizeof(pxa_dma_desc);
  70                 dma_desc->ddadr = next_desc_phys;
  71                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  72                         dma_desc->dsadr = dma_buff_phys;
  73                         dma_desc->dtadr = rtd->params->dev_addr;
  74                 } else {
  75                         dma_desc->dsadr = rtd->params->dev_addr;
  76                         dma_desc->dtadr = dma_buff_phys;
  77                 }
  78                 if (period > totsize)
  79                         period = totsize;
  80                 dma_desc->dcmd = rtd->params->dcmd | period | DCMD_ENDIRQEN;
  81                 dma_desc++;
  82                 dma_buff_phys += period;
  83         } while (totsize -= period);
  84         dma_desc[-1].ddadr = rtd->dma_desc_array_phys;
  85
  86         return 0;
  87 }
  88
  89 static int pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
  90 {
  91         struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
  92
  93         *rtd->params->drcmr = 0;
  94         snd_pcm_set_runtime_buffer(substream, NULL);
  95         return 0;
  96 }
  97
  98 static int pxa2xx_pcm_prepare(struct snd_pcm_substream *substream)
  99 {
 100         struct pxa2xx_pcm_client *client = substream->private_data;
 101         struct snd_pcm_runtime *runtime = substream->runtime;
 102         struct pxa2xx_runtime_data *rtd = runtime->private_data;
 103
 104         DCSR(rtd->dma_ch) &= ~DCSR_RUN;
 105         DCSR(rtd->dma_ch) = 0;
 106         DCMD(rtd->dma_ch) = 0;
 107         *rtd->params->drcmr = rtd->dma_ch | DRCMR_MAPVLD;
 108
 109         return client->prepare(substream);
 110 }
 111
 112 static int pxa2xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 113 {
 114         struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
 115         int ret = 0;
 116
 117         switch (cmd) {
 118         case SNDRV_PCM_TRIGGER_START:
 119                 DDADR(rtd->dma_ch) = rtd->dma_desc_array_phys;
 120                 DCSR(rtd->dma_ch) = DCSR_RUN;
 121                 break;
 122
 123         case SNDRV_PCM_TRIGGER_STOP:
 124         case SNDRV_PCM_TRIGGER_SUSPEND:
 125         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 126                 DCSR(rtd->dma_ch) &= ~DCSR_RUN;
 127                 break;
 128
 129         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 130                 DCSR(rtd->dma_ch) |= DCSR_RUN;
 131                 break;
 132
 133         default:
 134                 ret = -EINVAL;
 135         }
 136
 137         return ret;
 138 }
 139
 140 static void pxa2xx_pcm_dma_irq(int dma_ch, void *dev_id, struct pt_regs *regs)
 141 {
 142         struct snd_pcm_substream *substream = dev_id;
 143         struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
 144         int dcsr;
 145
 146         dcsr = DCSR(dma_ch);
 147         DCSR(dma_ch) = dcsr & ~DCSR_STOPIRQEN;
 148
 149         if (dcsr & DCSR_ENDINTR) {
 150                 snd_pcm_period_elapsed(substream);
 151         } else {
 152                 printk( KERN_ERR "%s: DMA error on channel %d (DCSR=%#x)\n",
 153                         rtd->params->name, dma_ch, dcsr );
 154                 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 155         }
 156 }
 157
 158 static snd_pcm_uframes_t pxa2xx_pcm_pointer(struct snd_pcm_substream *substream)
 159 {
 160         struct snd_pcm_runtime *runtime = substream->runtime;
 161         struct pxa2xx_runtime_data *rtd = runtime->private_data;
 162         dma_addr_t ptr = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
 163                          DSADR(rtd->dma_ch) : DTADR(rtd->dma_ch);
 164         snd_pcm_uframes_t x = bytes_to_frames(runtime, ptr - runtime->dma_addr);
 165         if (x == runtime->buffer_size)
 166                 x = 0;
 167         return x;
 168 }
 169
 170 static int
 171 pxa2xx_pcm_hw_rule_mult32(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
 172 {
 173         struct snd_interval *i = hw_param_interval(params, rule->var);
 174         int changed = 0;
 175
 176         if (i->min & 31) {
 177                 i->min = (i->min & ~31) + 32;
 178                 i->openmin = 0;
 179                 changed = 1;
 180         }
 181
 182         if (i->max & 31) {
 183                 i->max &= ~31;
 184                 i->openmax = 0;
 185                 changed = 1;
 186         }
 187
 188         return changed;
 189 }
 190
 191 static int pxa2xx_pcm_open(struct snd_pcm_substream *substream)
 192 {
 193         struct pxa2xx_pcm_client *client = substream->private_data;
 194         struct snd_pcm_runtime *runtime = substream->runtime;
 195         struct pxa2xx_runtime_data *rtd;
 196         int ret;
 197
 198         runtime->hw = pxa2xx_pcm_hardware;
 199
 200         /*
 201          * For mysterious reasons (and despite what the manual says)
 202          * playback samples are lost if the DMA count is not a multiple
 203          * of the DMA burst size.  Let's add a rule to enforce that.
 204          */
 205         ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
 206                                   pxa2xx_pcm_hw_rule_mult32, NULL,
 207                                   SNDRV_PCM_HW_PARAM_PERIOD_BYTES, -1);
 208         if (ret)
 209                 goto out;
 210         ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
 211                                   pxa2xx_pcm_hw_rule_mult32, NULL,
 212                                   SNDRV_PCM_HW_PARAM_BUFFER_BYTES, -1);
 213         if (ret)
 214                 goto out;
 215
 216         ret = -ENOMEM;
 217         rtd = kmalloc(sizeof(*rtd), GFP_KERNEL);
 218         if (!rtd)
 219                 goto out;
 220         rtd->dma_desc_array =
 221                 dma_alloc_writecombine(substream->pcm->card->dev, PAGE_SIZE,
 222                                        &rtd->dma_desc_array_phys, GFP_KERNEL);
 223         if (!rtd->dma_desc_array)
 224                 goto err1;
 225
 226         rtd->params = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
 227                       client->playback_params : client->capture_params;
 228         ret = pxa_request_dma(rtd->params->name, DMA_PRIO_LOW,
 229                               pxa2xx_pcm_dma_irq, substream);
 230         if (ret < 0)
 231                 goto err2;
 232         rtd->dma_ch = ret;
 233
 234         runtime->private_data = rtd;
 235         ret = client->startup(substream);
 236         if (!ret)
 237                 goto out;
 238
 239         pxa_free_dma(rtd->dma_ch);
 240  err2:
 241         dma_free_writecombine(substream->pcm->card->dev, PAGE_SIZE,
 242                               rtd->dma_desc_array, rtd->dma_desc_array_phys);
 243  err1:
 244         kfree(rtd);
 245  out:
 246         return ret;
 247 }
 248
 249 static int pxa2xx_pcm_close(struct snd_pcm_substream *substream)
 250 {
 251         struct pxa2xx_pcm_client *client = substream->private_data;
 252         struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
 253
 254         pxa_free_dma(rtd->dma_ch);
 255         client->shutdown(substream);
 256         dma_free_writecombine(substream->pcm->card->dev, PAGE_SIZE,
 257                               rtd->dma_desc_array, rtd->dma_desc_array_phys);
 258         kfree(rtd);
 259         return 0;
 260 }
 261
 262 static int
 263 pxa2xx_pcm_mmap(struct snd_pcm_substream *substream, struct vm_area_struct *vma)
 264 {
 265         struct snd_pcm_runtime *runtime = substream->runtime;
 266         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 267                                      runtime->dma_area,
 268                                      runtime->dma_addr,
 269                                      runtime->dma_bytes);
 270 }
 271
 272 static struct snd_pcm_ops pxa2xx_pcm_ops = {
 273         .open           = pxa2xx_pcm_open,
 274         .close          = pxa2xx_pcm_close,
 275         .ioctl          = snd_pcm_lib_ioctl,
 276         .hw_params      = pxa2xx_pcm_hw_params,
 277         .hw_free        = pxa2xx_pcm_hw_free,
 278         .prepare        = pxa2xx_pcm_prepare,
 279         .trigger        = pxa2xx_pcm_trigger,
 280         .pointer        = pxa2xx_pcm_pointer,
 281         .mmap           = pxa2xx_pcm_mmap,
 282 };
 283
 284 static int pxa2xx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 285 {
 286         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 287         struct snd_dma_buffer *buf = &substream->dma_buffer;
 288         size_t size = pxa2xx_pcm_hardware.buffer_bytes_max;
 289         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 290         buf->dev.dev = pcm->card->dev;
 291         buf->private_data = NULL;
 292         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 293                                            &buf->addr, GFP_KERNEL);
 294         if (!buf->area)
 295                 return -ENOMEM;
 296         buf->bytes = size;
 297         return 0;
 298 }
 299
 300 static void pxa2xx_pcm_free_dma_buffers(struct snd_pcm *pcm)
 301 {
 302         struct snd_pcm_substream *substream;
 303         struct snd_dma_buffer *buf;
 304         int stream;
 305
 306         for (stream = 0; stream < 2; stream++) {
 307                 substream = pcm->streams[stream].substream;
 308                 if (!substream)
 309                         continue;
 310                 buf = &substream->dma_buffer;
 311                 if (!buf->area)
 312                         continue;
 313                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 314                                       buf->area, buf->addr);
 315                 buf->area = NULL;
 316         }
 317 }
 318
 319 static u64 pxa2xx_pcm_dmamask = 0xffffffff;
 320
 321 int pxa2xx_pcm_new(struct snd_card *card, struct pxa2xx_pcm_client *client,
 322                    struct snd_pcm **rpcm)
 323 {
 324         struct snd_pcm *pcm;
 325         int play = client->playback_params ? 1 : 0;
 326         int capt = client->capture_params ? 1 : 0;
 327         int ret;
 328
 329         ret = snd_pcm_new(card, "PXA2xx-PCM", 0, play, capt, &pcm);
 330         if (ret)
 331                 goto out;
 332
 333         pcm->private_data = client;
 334         pcm->private_free = pxa2xx_pcm_free_dma_buffers;
 335
 336         if (!card->dev->dma_mask)
 337                 card->dev->dma_mask = &pxa2xx_pcm_dmamask;
 338         if (!card->dev->coherent_dma_mask)
 339                 card->dev->coherent_dma_mask = 0xffffffff;
 340
 341         if (play) {
 342                 int stream = SNDRV_PCM_STREAM_PLAYBACK;
 343                 snd_pcm_set_ops(pcm, stream, &pxa2xx_pcm_ops);
 344                 ret = pxa2xx_pcm_preallocate_dma_buffer(pcm, stream);
 345                 if (ret)
 346                         goto out;
 347         }
 348         if (capt) {
 349                 int stream = SNDRV_PCM_STREAM_CAPTURE;
 350                 snd_pcm_set_ops(pcm, stream, &pxa2xx_pcm_ops);
 351                 ret = pxa2xx_pcm_preallocate_dma_buffer(pcm, stream);
 352                 if (ret)
 353                         goto out;
 354         }
 355
 356         if (rpcm)
 357                 *rpcm = pcm;
 358         ret = 0;
 359
 360  out:
 361         return ret;
 362 }
 363
 364 EXPORT_SYMBOL(pxa2xx_pcm_new);
 365
 366 MODULE_AUTHOR("Nicolas Pitre");
 367 MODULE_DESCRIPTION("Intel PXA2xx PCM DMA module");
 368 MODULE_LICENSE("GPL");